Automatic brake for hoisting-machines.



. No. 738,556. PATBNTED SEPT. 8,-19 03.

; R. L. LOVELL 8: P. P. PALEN.

AUTOMATIC BRAKE FOR HOISTING MACHINES.

APPLIQATIOI nun KAY 12. 1903.

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Q6 Q o o 0 E O O I 9 i 40 i Wflnaoow m: mums FETEES co, Puma-mum. wAswmaTm n c No. 738,556. PAIIEIENTED SEPT. 8, 1903. K. Ii. LOVELL 6: F. P. PA LBN'. AETQMATIG BRAKE FOR HOISTING MAGHINBS.

APPLICATION FILED MAY 12, 1903.

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01 QKJMZZZ? No. 738,556. PATENTBD SEPT. 8, 1903.

R. L. LOVELL & P. P.'PALEN.

AUTOMATIC BRAKE FOR HOISTING MACHINES.

APPLICATION FILED MAY 12. 1903.

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ivo. 738,556.

UNITED STATES l atented September 8, 1903. PATENT OFFICE.

RALPH L. LOVELL AND FREDERICK P. PALEN, OF NEWPORT NEWS,

. VIRGINIA.

AUTOMATIC BRAKE FOR HOlSTlNG-MACHINES.

SPECIFICATION forming part of Letters Patent N 0. 738,556, dated September 8, 1903.

Application filed May 12, 1903. Serial No. 156,860. (No model.)

Be it known that we, RALPH L. LOVELL and I FREDERICK P. PALEN, citizens of the United States, both residing at Newport News, in the county of Warwick, State of Virginia, have invented a new and useful Improvement in Automatic Brakes for Use on Hoisting-Machines, of-which the following is a specification.

Our invention consists of an improved automatic brake for use in a hoisting-machine, which acts to hold the suspended load at any desired point and to resist its descent.

It further consists of novel details of con struotion hereinafter set forth.

Figure 1 represents a top plan view of our device. Fig.2 represents the same device partly in vertical'section. Fig. 3 represents an elevation of a friction-cone and ratchet employed. Fig. 4 represents, partly in elevation and partly in vertical section, a modified form of the essential features of our device.

Similar numerals of reference indicate corresponding parts in the figures.

Referring to Figs. 1, 2, and 3 of the drawings, 1 designates the base, provided with internal gear-teeth 2. 3 is a step-plate in which is stepped a-mast 4. To this mast may of course be attached the usual boom or gaff.

I (Not shown.) Mounted on the step-plate 3 is a motor 5, connected by suitable gear 6 and worm 7 to connected spur wheels or pinions 8, the teeth of the latter meshing with the teeth 2 of thebase 1. Any other convenient means for swinging the load by means of the rotation of the mast and step-plate may be used. The step-plate 3 also carries a motor 9, connected by gears 10 to a worm-shaft 11, to which is suitably secured a worm l2. I prefer, for reasons hereinafter apparent, to

forge or mount on the-shaft 11 a collar 13, against which the worm 12 thrusts. Meshing with the worm12 is a worm-wheel 14, which serves to rotate a hoisting-drum 15, suitably supported on the step plate 3. From the drum 15 leads a rope 16 to the supported load. (Not shown.) Near one end of the shaft 11 is secured a ratchet-wheel 17, in the teeth of which engages a plurality of pawls 18, connected to a friction-cone 19. The cone 19 bears against the inner surface of a stationary cone-case 20.

Figs. 2 and 3 of the drawings clearly show that a rotation of the shaft 11 in the direction to wind the rope 16 on the drum 15, and

be so adjusted as to produce any desired amount of friction. It is evident that this friction varies directly with the load weight,

any increase in which causes a prop ortionately greater thrust of the shaft 11 toward the cone-case 20. It is of course desirable that the friction of the cone in its case shall exceed the gravitative force of the load, whereby the load is safely held at any desired point. By making the friction equal to twice the load the duty of the motor is substantiallythe same when running in either direction.

In Fig. i of the drawings we have shown the friction device directly connected to the shaft of the drum, the enlarged shaft 22 of which is cut off at an angle corresponding to that of a subsidiary shaft 23, running in the same bearing 24 to which the ratchet-17 is attached. It is clear that when the pawls 18 are locked with the ratchet 17, as in lowering the load, the end of the shaft 22 will ride as a cam on the end of the shaft 23, thereby producing the desired thrust of the cone 19 into the case 20.

It will be evident that various changes may be made in the art which may come Within the scope of our invention ,and we do not therefore desire to be limited to the exact construction herein shown anddescribed.

Having thus described our invention, what we claim as new, and desire to secure by Letters Patent, is-

1. An automatic brake for a hoisting-ma chine consisting of a friction-cone and a case,-

a shaft on which one of said brake portions is loosely mounted, a ratchet mounted on said shaft and engaged with said brake portion when the drum of said machine is rotated in one direction only, and means connected with said drum for producing on said shaft a longitudinal thrust, Variable with the Weight of the suspended load.

2. In a hoisting-machine, a power-actuated shaft, a drum driven by said shaft, a frictioncone loosely mounted on said shaft, a casein which said cone rotates and means for looking said cone to said shaft, the parts being so arranged that the rotation of said drum in a direction to lower a suspended load, acts to lock said cone to said shaft, and to thrust said shaft toward said case.

3. In a hoisting-machine, a power-actuated shaft, a worm secured to said shaft, a hoisting-drum driven by said worm, a frictioncone loosely mounted on said shaft, a casein which said cone rotates, and means for looking said cone to said shaft, the parts being so arranged that the rotation of said drum in the direction to lower a suspended load, acts to lock said cone to said shaft and to thrust said shaft toward said case.

RALPH L. LOVELL. FREDERICK P. PALEN.

Witnesses:

' LEROY F. Booes,

HERBERT L. SMITH. 

